The whole charger (it has no separate power transformer and plugs directly into a power outlet) is almost exactly the same size as the CA-570 charger that comes with the HV10, but since it is a standalone charger, it does not have to be plugged into the HV10. It also comes with a cigarette lighter adaptor and a European plug adaptor. It took about 2 hrs to charge a BP-315. This charger (or other, very similar looking chargers) is available from other sources, but I was very happy with BatteryBarn's service when I purchased their replacement for the BP-315.

The charger is made by CTA Digital Accessories (www.ctadigital.com)
MR-BP208 Digital Camcorder Mini Battery Charger
For Canon BP-208, BP-308, BP-315 batteries (I should think it would also work for the BP-310)

I bought a Samsonite "Trekking Premium DFV 33" for my trip to the Galapagos Islands earlier this month. I was looking for the most compact and lightweight case which I could wear on my belt. I didn't feel the need to lug the charger or 10 tapes around with me on my daily expeditions so they stayed in my suitcase. The Samsonite provides a snug fit for the HV10 which I also found is accomodated best when inserted upsidedown. There are side pockets at each end which are the perfect size to house a BP315 each. The front pocket will take one spare cassette (in its case) while there is also a rear zipped pocket which I used to carry a small ziplok plastic bag so I could seal up the HV10 when travelling to and from shore by dinghy. The case also has an integral rain hood which can be pulled out of its dedicated compartment when necessary. A shoulder strap is also supplied but I found using the sewn on belt loops a more efficient arrangement. Access to the camera is by twin zips. When unzipped, the case top hinges forward which felt a bit strange at first. By doing this Samsonite intends you to access the camcorder without having to work over the top of the lid. Quite obvious when you think about it.
Here in the UK the case retails for GBP25 but is available from Amazon for about half that price. I'm sure Froogle will throw up a convenient source in the U.S.
Happy Holidays,
Trevor.